Photochemical Reaction Products of Polycyclic Aromatic Hydrocarbons

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Photochemical Reaction Products of Polycyclic Aromatic Hydrocarbons Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2011 Photochemical Reaction Products of Polycyclic Aromatic Hydrocarbons Adsorbed at an Air-Water Interface Franz Stefan Ehrenhauser Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Chemical Engineering Commons Recommended Citation Ehrenhauser, Franz Stefan, "Photochemical Reaction Products of Polycyclic Aromatic Hydrocarbons Adsorbed at an Air-Water Interface" (2011). LSU Doctoral Dissertations. 530. https://digitalcommons.lsu.edu/gradschool_dissertations/530 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. PHOTOCHEMICAL REACTION PRODUCTS OF POLYCYCLIC AROMATIC HYDROCARBONS ADSORBED AT AN AIR-WATER INTERFACE A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Cain Department of Chemical Engineering by Franz Stefan Ehrenhauser Dipl. Ing., Johannes Kepler University, Linz, Austria, 2009 December 2011 Die hohe Kraft Der Wissenschaft, Der ganzen Welt verborgen! Und wer nicht denkt, Dem wird sie geschenkt, Er hat sie ohne Sorgen. Johann Wolfgang von Goethe, Faust, 1808 To the patience of my parents and my loving wife ii ACKNOWLEDGEMENTS I would like to thank first and foremost my advisor Dr. Mary J. Wornat for her support and her guidance. Thanks to her, doors and opportunities have opened for me, which I would have otherwise never realized. I also have to express my deepest gratitude to Dr. Kalliat T. Valsaraj, who acted as my co-advisor during these years, for his patience and continuous support. I would also like to thank my committee members, Dr. James J. Spivey, Dr. Francisco Hung and Dr. Maud Walsh for their time. I have to thank all my colleagues and co-workers for their help, their inspirations through fruitful discussions and their additional perspectives. I want to especially thank Dr. Jing Chen, to whom I am greatly indebted to, as without her work the extent of this dissertation would not have been possible. I also owe gratitude to all the members of the department of chemical engineering, which took care, that either ideas could be realized in the laboratory (Paul Rodriguez, Joe Bell, Fred McKenzie), or that the bureaucracy did not stand in the way (Darla Dao, Melanie McCandless and Danny Fontenot). I want to thank my parents for their patience and their continuous support. A very special thanks bears to my beloved wife Daira, who stood by me these years, being my big support in any difficult situation. I would like to acknowledge funding from NSF (Grant ATM 0355291 and Grant ATM 0907261), the Air Force Office of Scientific Research for providing funding for two HPLC instruments (DURIP Grant FA9550-05-1-0253 and DURIP Grant FA9550-08-1-0281), the LSU Graduate School for providing additional scholarships, as well Dr. Charles Coates, whose generosity in form of the Dr. Charles E. Coates Scholar Research Award allowed me to collect new experiences and present my work worldwide. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ........................................................................................................... iii LIST OF TABLES ........................................................................................................................ vii LIST OF FIGURES ..................................................................................................................... viii ABSTRACT ................................................................................................................................. xiv 1. INTRODUCTION .......................................................................................................................1 1.1 Polycyclic Aromatic Hydrocarbons .......................................................................................2 1.2. PAH Photodegradation .........................................................................................................5 1.2.1. Degradation Products of PAH in Bulk Phases ...................................................................9 1.2.2. Degradation Products of PAH in Thin Water Films ........................................................10 1.3. Environmental Impacts of Volatile PAH and Their Oxidation Products ...........................12 1.3.1. Health Effects of Volatile PAH and Their Oxidation Products ...................................12 1.3.2. Environmental Effects of Volatile PAH and Oxidation Products ...............................13 1.4. Objective and Structure of Thesis .......................................................................................14 2. ANALYSIS OF UV-OXIDATION PRODUCTS OF PAH – METHOD DEVELOPMENT .................................................................................15 2.1 HPLC – Method Development ............................................................................................17 2.2. Online Sample Concentration .............................................................................................21 2.3. UV Absorption as Detection Method for Oxygenated Polycyclic Aromatic Compounds ........................................................................................................25 2.4. APPI-MS .............................................................................................................................29 2.5. APPI-MS Method Development .........................................................................................31 2.5.1. APPI Source Optimization ...............................................................................................33 2.5.2. Dopant Delivery System ..................................................................................................39 2.5.2.1. Design of the Dopant Delivery System ....................................................................40 2.5.2.2. Dopant Selection .......................................................................................................45 2.5.2.3. Ionization Performance of Benzene as Dopant .........................................................49 2.6. APPI-MS Spectra ................................................................................................................53 2.6.1. Polycyclic Aromatic Hydrocarbons .............................................................................54 2.6.2. Hydroxyl-Substituted Polycyclic Aromatic Hydrocarbons .........................................55 2.6.3. Alcohols .......................................................................................................................56 2.6.4. Aromatic Ketones ........................................................................................................57 2.6.5. Carboxylic Acids and Esters ........................................................................................58 2.6.6. Aldehydes ....................................................................................................................60 2.6.7. APPI-MS Spectra for the Identification of OPAC .......................................................61 3. EXPERIMENTAL SETUP ........................................................................................................64 3.1. Thin-Film Reactor ...............................................................................................................64 3.2. Bulk-Phase Reactor .............................................................................................................69 3.3. Sample Analysis .................................................................................................................70 iv 4. PHOTOOXIDATION PRODUCTS OF POLYCYCLIC AROMATIC HYDROCARBONS ............................................................................................72 4.1. Naphthalene ........................................................................................................................72 4.2. Phenanthrene .......................................................................................................................74 4.3. Pyrene .................................................................................................................................81 4.4. Acenaphthene ......................................................................................................................83 4.5. 9H-Fluorene ........................................................................................................................85 4.6. Summary .............................................................................................................................93 5. PHOTOOXIDATION OF 9H-FLUORENE IN THIN WATER FILMS ..................................95 5.1. Uptake of 9H-Fluorene onto Water Films ..........................................................................95 5.2 Photooxidation of 9H-Fluorene in Thin-Water Films .........................................................98 5.3. Discussion .........................................................................................................................103
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